Administration of antenatal corticosteroids to accelerate fetal lung maturity and reduce the incidence of respiratory distress syndrome in premature human fetuses was first described by Liggins and Howie in 1972. Their findings were subsequently confirmed by several others. Although the efficacy of this treatment is well established, there is relatively little information from controlled studies available regarding the effects of single course and multiple course therapy with antenatal corticosteroids on the neonatal adrenal gland. The objective of this study is to examine the effects of single course betamethasone versus multiple weekly courses of antenatal betamethasone on the neonatal adrenal in the first week of life using the ACTH stimulation test.